


Little Kitty Kat

by waitingforjudas



Series: Judas' Kinktober 2019 [9]
Category: Teen Wolf (TV)
Genre: Alpha Derek Hale, Costumes, Everyone Is Alive, F/F, Female Derek Hale/Female Stiles Stilinski, Genderswap, Kinktober, Kinktober 2019, Kitten Derek, Mating Cycles/In Heat, Nobody is Dead, Pet Play, Scissoring, True Mates, scissoring is not all it's cracked up to be, temporarily so anyway
Language: English
Status: Completed
Published: 2019-10-10
Updated: 2019-10-10
Packaged: 2020-11-28 20:16:47
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,653
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20972435
Author URL: https://archiveofourown.org/users/waitingforjudas/pseuds/waitingforjudas
Summary: Stiles wants to put this sudden, city-wide genderswap to good use with Derek, but that would require telling Derek that he’s into him. But since Derek’s completely closed off since the swap, Stiles has even less of a chance now than he otherwise would with a knockout like Derek Hale.Right?Written for Kinktober 2019 prompts: Pet Play, Scissoring, and Costumes.





	Little Kitty Kat

**Author's Note:**

> I am a cis person and have never questioned my gender. While I have done research, I could have easily missed something or said something insensitive. If I have written something offensive in this story, I am always ready to listen and change things. The last thing I want to do is write something that hurts somebody.
> 
> _Written for Kinktober 2019. Prompt list can be found at https://twitter.com/NihilistShiro/status/1162794889970511872._

Stiles was kind of loving being a woman, honestly. His dad was really struggling, as was just about everybody else he knew. 

Scott was having a surprisingly rough time, actually, which Stiles really didn’t expect, given how much Scott seemed like this big, happy puppy that never got sad, ever. 

Erica and Boyd seemed to be enjoying themselves, and Isaac was the gangliest woman that Stiles had ever seen—and Lydia, of course, looked stunning, as always. 

Even Jackson, though, was taking it better than Derek was. 

Mostly because Stiles had only seen Derek once in the past eighteen days, and it had been at the very beginning of all this, when Stiles was about to admit that he had feelings for Derek, and then—out of fucking nowhere—the entire town genderswapped. 

Deaton had reassured Stiles that it was unrelated, but still. The timing had sucked. 

Derek as a woman wasn’t quite as stunning as Derek as a man, but that could’ve been because Stiles had only gotten a glimpse that spanned about four or five seconds before Derek had snapped at him, in an even more improbably high voice than normal, to “Get the hell out, Stiles!”

Here was the thing—Stiles didn’t _want_ to push Derek. But at this point, he had more than a few questions to ask him, and, well—Derek was just going to have to stick a bag over his head, because Stiles needed some answers. 

And _that_ was why Stiles was beating down Derek’s door, yelling and shouting and trying to be as obnoxious and un-ignorable as possible. 

“I’ll call the cops!” Derek shouted from somewhere inside his house. 

“My father _is_ the cops!”

“Then I’ll call an ambulance.” 

That was a lot closer. 

“Wait, why the hell do I need an ambulance?” Stiles could practically see the smirk on Derek’s face. “Dude, let me in!”

“I’m not a dude,” Derek said, softly—a few feet away from the door at most. 

“Is that what this weird avoidance thing is about? Dude, I’m not a dude either. At the moment, anyway. You know, Scott’s not taking this well, either. I swear, I’m getting a call from him crying at _least_ twice a day about how his dick’s gone and he misses ‘Scott Junior.’ Also, what kind of weirdly uncreative name for a penis is that? I mean, I call _mine_—”

The door flew open to reveal Derek, scowling viciously. “Don’t finish that sentence.”

Stiles grinned. “Good to see you, big guy.”

Derek rolled his eyes but stepped aside to let Stiles in. “What do you want, Stiles?”

Stiles’ knee-jerk response was, of course, “You,” but other than that… “I need to talk to you about something I read in the bestiary.”

Derek scowled deeper. “I told you I didn’t want to talk about why werewolves were uncircumcised anymore.”

“Not that—although, it is kind of weird— No, I wanted to ask you about something else. Sort of related to that, but not _exactly_ that—”

“The point, Stiles.”

“Yeah, sorry, of course. Okay, so, like—” Stiles sat down on the couch, tossing his backpack onto the floor as he kicked his legs up— “how, exactly, does rut work?”

Derek made a pained noise. “_Stiles_.”

“Because as far as I can tell, it’s not that common, but I can’t figure out why, because apparently, the Argents weren’t too great at intimate discussions with—”

“Stiles, I’m not—”

“Okay, like, I wouldn’t mention it except that you’re kind of exhibiting pre-rut symptoms. I mean, they cross over with other things, but—”

“The _point_, Stiles.”

“What _causes_ rut?”

Derek blinked at him, and then let out a heavy sigh. “I should have just let you talk about your penis,” he muttered. 

“Who, Mini Mischief?”

“Why,” Derek said, more to the room at large than to Stiles specifically. 

“My real name sounds like Mischief, and my dick gets into mischief, as well as mister-chief, and—”

“You’re gay?”

“That’s what you got away from that?” Stiles snorted. “I thought it was a great pun.”

“Are you gay?”

Stiles frowned at him. “Not… exactly. I like both. Or all. Or however you want to define, ‘always horny, always ready for action.’”

Derek stared at him for long enough that Stiles really started fidgeting. 

“Dude, I wouldn’t have mentioned it if I thought you were going to be upset about it, but—”

“Not upset.”

“Okay— Uh— Uncomfortable with it, then—”

“Not uncomfortable.”

Stiles threw up his hands in frustration. “Then what?”

“I’m. Um. Bi.”

“Baby, bi, bi, bi!” Stiles clapped a hand over his mouth. “I’m so sorry, that wasn’t supportive at all, was it?”

Derek laughed. “Don’t worry about it, Stiles.”

“Okay, so. Rut—”

“Stiles.”

“Yup?”

“It’s….” Derek sighed, leaning on the back of one of the supremely plush armchairs that Erica had thrown a fit over until he agreed to purchase. (Stiles gave her _major_ kudos for that move.) “Rut is complicated, Stiles. There’s at least a dozen factors at play at any one time.”

“Have you ever been in rut?”

“No.” Derek shook his head. “Never.”

“Will you—”

“The— It— Do you have a pen and paper?”

Stiles grinned, pulling said items out of his backpack. “I am _always_ prepared.”

Derek groaned, but took them anyway. “You’re always ridiculous.”

He shrugged. “No problem with that. Are you making a flow chart?”

Derek huffed. “Maybe.”

“Cool. Cool, that’s… cool.”

Stiles twiddled his thumbs for a few minutes before Derek abruptly handed him the piece of paper, capping the pen. “That’s the baseline. No true mate met, prepubescent, no alpha shift, minimally controlled beta shift.”

“Those are the main factors?”

He shook his head. “No, the main factor is the true mate. The others are conditions that also have to be met.”

“So—”

“So if a wolf met their true mate, they would both have to be post-pubescent, for instance. If the wolf had an alpha shift, that would have to be fully controlled in addition to the beta shift.”

“You have an alpha shift, right?”

Derek shrugged. “Yeah.”

“So you meet the conditions, right?”

Derek stilled. “I— I have a controlled alpha shift.”

“No, but, like—if you had a true mate—”

“I do have a true mate.”

“Really? Who is it?”

“The— All wolves have one,” Derek said, visibly closing off again. “It’s not a matter of having one or not, it’s a matter of meeting them or not.”

“Have you met yours?”

Derek gulped, his Adam’s apple bobbing hard. 

“Are you okay, Derek? You’re acting—”

“I’m fine. Um. The mate would have to—” Derek stopped, shifting and wiping his brow. “Would have to— Be acknowledged. By the wolf. And the. Mate.”

“Derek— Hey, Derek, do you need me to call someone?” Stiles stood, stepping forward. 

“Don’t! Don’t, just— I’m fine. Call— Call Scott.”

Stiles hesitated, but reached for his phone. “What’s going on?” 

“It’s— You’re right. You’re right, I was— In—” Derek’s eyes flashed red and he shifted, fangs lengthening, brow protruding. “Pre-rut. I’m—I’m sorry.”

“No, that’s—” Then something clicked together. Stiles lowered the phone slowly. “Who’s your mate?”

“It’s not im—”

“It’s someone you acknowledged, isn’t it? As a possibility?”

Derek whimpered, dropping his head to his forearms. His hair covered the sides of his face so Stiles couldn’t get a good look at his face, but Stiles had a pretty good idea of what he’d see. 

“Derek, is it me.”

Derek nodded. “I’m so sorry, Stiles, it’s not something I can control.” 

Coming from anybody else on the _planet_, Stiles would take offense to that. Coming from Derek?

“My understanding,” Stiles said carefully, “is that wolves going into their first rut cope in… eccentric ways.”

“Yes, it’s—” Derek cut himself off with a low moan. “You should leave.”

“Is it because you want me to leave?” 

Derek shook his head. “But you should.”

“If you want me to leave, I will, Derek. But I think… maybe… you don’t. So can I ask, instead, how you’re going to cope?” 

Derek mumbled something into the back of the chair, slumping forward more. 

The bestiary, for all its flaws, had had a fair amount of information on the various ways that wolves coped with initial ruts. It was usually something to do with a fetish—not always—but it built off of something that made them feel safer during sex. For some—a surprising number, actually—it was being tied up with wolfsbane-infused restraints so that they didn’t worry about injuring their partner. For many, it was being cared for in some way. Some were littles, and would pretty much regress completely. Others…. 

Well, it varied. 

“Can you repeat that?” Stiles said, moving closer—slowly, in case Derek decided to change his mind. 

“Gonna— Be a cat.”

Stiles blinked. “That’s all? Do you actually shift into a cat, or do you—”

“Pretend.” Derek groaned again. 

“That’s fine. More than, actually. I get the feeling that you’d made a cute cat. Are you a cat or a kitten?”

Derek turned bright red. 

“I’m assuming kitten.”

He nodded. 

“Okay. Tell you what—let’s get you in bed and get you dressed up so you can be a kitten, okay? Do you—”

“I don’t know how to do this,” Derek gasped, grabbing onto Stiles’ arm for support the moment it was offered. 

“I’m here, Derek. Okay? I’ve got you.”

“No, I don’t— I always thought— I thought I’d be a _man_,” Derek choked out, stumbling with Stiles to the bedroom. 

“Well, lucky for you, I know all about the mechanics of rut in male _and_ female bodies, and guess what? It’s mostly just getting orgasms.”

“I have to— It can’t—”

Stiles helped Derek onto the bed. “Go ahead.”

“I have to move.”

Stiles frowned. “Now?”

Derek laughed breathily, shaking his head. “No. No, not now, to—to come.”

“Oh,” Stiles said. “_Oh_. I can’t just eat you out or fuck you, can I?”

“It’s never easy, Stiles. You can go, I’ll take care of—”

“Hey,” Stiles said, voice hardening. “I’m here to take care of you, Derek. No matter what. I mean, hey, I’ve always been curious about scissoring.”

“I’m not gonna—” Derek grunted. “Maybe I’ll scissor you.”

“Do you have a costume or something for when you’re a kitten?”

Derek nodded hesitantly. “In the nightstand.”

Stiles opened it and pulled out a pair of soft, black cat ears on a headband and a long, fuzzy black tail on—

“You use these often?” Stiles said, and cleared his throat. His voice had gotten too thick. 

Derek flushed. “You can—”

“I’m not leaving, Derek. Not unless you want me to. Okay?”

Derek nodded slowly. “Okay.” 

“Good. Do you have a name you want to be referred to while you’re a kitten?”

“Der-Bear,” he said softly.

“And are you male or female or some other pronoun in your headspace?”

“Male. This is a fucking mindfuck.”

Stiles flicked Derek’s thigh, and Derek’s legs fell open, letting Stiles get a good look up Derek’s loose black short shorts. 

“You’re not— Okay. Hmm. I was—gonna say—not to curse, because kittens aren’t supposed to curse, but— Shit. Okay. Okay. Um.”

Derek was grinning at him. “What?”

“Put on your damn ears,” Stiles said, the only heat in it his heavy arousal. 

Derek took them, lifting his head enough to tuck them behind his ears, arranging his long, straight hair around them until they looked like they’d just sprouted out of his head one day. 

“You look really hot,” Stiles rasped. “And I hope you know that it’s not because you’re a woman. You’re a hot woman, too, but goddamn, when you’re a man….”

Derek snorted. “Will you come here before another wave hits?”

Stiles smiled. “Of course I will. Just—are you sure about everything?”

“I should be asking you that,” Derek said. 

“You have been, though. I’m asking you now.”

Derek shrugged. “It’s not like I have much else that I could really do, right?”

Stiles frowned. “That’s… not exactly as encouraging as I think you intended for it to be, Derek.”

“Look, just— I accepted you as my mate a long time ago. Worryingly long ago, actually. It’s just— I didn’t think that you’d ever consider me as a possibility, honestly. So I mean— I don’t know. You’re not what I’d expected, Stiles, but that’s a good thing.”

“Are you sure?”

“You accepted me as your mate a few minutes ago. Can I ask what changed for you?”

Stiles shrugged, too, sitting down on the bed slowly. “I mean… it’s just.… You’re bi. You might, in some world, be attracted to me.”

“I am.”

“I got that, dumbass. No, I’m just— I’m just saying. It didn’t feel like even sort of a possibility for a long time. I’m glad that it’s changed from that.”

“Me, too.” And with that, like all that the next wave of rut needed was a confirmation of their mutual desire to fuck, Derek groaned, clutching at his lower stomach. “It’s— Shit. I’m fine.”

“Let’s get your plug in, okay?” Derek nodded, obviously tense—too tense to get it in without hurting him. “Hey. Roll over, okay? Do you want to take off your shorts or do you want—“

“Take ‘em off,” Derek said, groaning as he followed Stiles’ order. 

“It’s okay,” Stiles said. “You’re good. Here, let’s— Where the fuck is your lube?”

“Top drawer, next to the— Well, it was next to the tail.”

“Of course it was,” Stiles muttered to himself. Derek was nothing if not well-prepared. And that was just who Derek was as a person, honestly. Endlessly prepared for everything. 

It was probably why this was throwing him so much. 

“I’m sorry about this,” Stiles said suddenly, and Derek tensed. 

“What are you talking about.”

“This— You went into rut, and it’s my fault, and—”

Derek relaxed again, taking the tub of—_Boy Butter_—from Stiles. “It’s as much my fault as it is yours. The only part I wasn’t hoping for was being in a different body for this.”

“You—you were hoping for this?”

Derek blushed, but he nodded shyly. “Kind of.” And with that, he unscrewed the lid, lubed up his fingers, and promptly stuck two in his ass. 

Stiles stared. 

“What? You stopped talking.”

Stiles blinked. “You have to ask why?”

“Oh, I— Sorry, sorry, yeah. It’s not exactly… appealing to see somebody shoving their—”

“You _what_?” Stiles sputtered. “You have _two fingers_ in your ass, Derek, how the _fuck_ is that not the most appealing thing I could ever see in my _life_?”

Derek flushed. “Can you hand me the tail?”

Stiles’ hands were shaking—_boy, wouldja look at that!_—as he picked up the tail (trying to make it less obviously reverent) and handed it to Derek. “Good?”

Derek took it, slipped his fingers out of his _loose_ hole and pressed the plug in, working it in slowly—and his rim bulged around the widest part before it just _sucked_ the rest in. 

Stiles may have moaned. 

Derek grinned at him. “Now get over here and scissor me, Stiles.”

Stiles leapt into action. 

###

“So maybe scissoring’s not all it looks like in porn,” Stiles said, irrationally disappointed. 

Derek cuffed the back of his head, just like a kitten swatting at him. 

Stiles grinned. “God, I love you, Der-Bear.”

Derek froze. 

Stiles froze. “Ooh. Ooh, I haven’t said that befo— Are you _purring_?”

Derek’s purring grew louder as he pushed his way into Stiles’ space, headbutting him and rubbing his cheeks all over Stiles’ face, neck, and chest. 

“You’re such a good kitten.”

And then, very suddenly, Derek was a man again, purring and butting into Stiles’ space, and Stiles smiled. 

He loved Derek in all forms, in all shapes, in all ways, but he had to admit that he was partial to the original. 

Stiles pressed a kiss to Derek’s forehead. “Beautiful, beautiful kitten, Der-Bear.”

Derek’s purrs filled the room. 

**Author's Note:**

> If you enjoyed, please consider leaving kudos or a comment. 
> 
> _This work was inspired by @NihilistShiro's Kinktober prompt list, available here: https://twitter.com/NihilistShiro/status/1162794889970511872 _


End file.
